A search for improved methods of removing contamiminants (reductases) from "state of the art" cytochrome oxidases is being made. The immunochemistry or reptilian and hymenoptera venom phospholipases is being studied by crossed immunoelectrophoresis as well as by the inhibition of activity resulting from the formation of antigen-antibody complexes. Aggregation of the porphyrins is being studied by coordinated spectral and ultracentrifugal studies. BIBLIOGRAPHIC REFERENCES: Nair, C., Hermans, J., Munjal, D. and Elliott, W.B. Temperature Stability of Phospholipase A Activity. I. Bee (Apis mellifera) Venom Phospholipase A2. Toxicon, 1976, in press. Nair, B.C., Nair, C. and Elliott, W.B. Temperature Stability of Phospholipase A Activity. II. Variations in Optimum Temperature of Venom Phospholipases A2 from Various Snakes. Toxicon, 1976, in press.